Yeah, I know "Clutching at straws" springs to mind but that is the only thing that comes close as there is not a thing anywhere on the 1901 census regarding them, and as Annette7 says, Lewis could have been wrote down instead of Leah as that is what Martha was sometimes called (she was known by that name for the census which followed.
George could have travelled around looking for work I suppose, 1891 farm servant in Austerfield, 1901 dock labourer in Goole, and then 10 years or so later he was a Hay cutter in Thorne.
All in close proximity to each other.